Most types of printing devices are equipped with items that are used up and/or have a life cycle during printing operations. These items can include one or more printing supplies, a printing media available to be printed on during the printing, a printing substance available for application to the printing media during the printing, toner available for application to the printing media during the printing, a laser printer drum, laser printer developer, a laser printer fuser, a printing media transfer belt, staples for stapling the printing media during the printing, a storage volume that is available to store paper that has been printed on by the printing device, and the like. These items are referred to herein as replaceable components. When a replaceable component is exhausted or at the end of its life cycle, the replaceable component must be replaced for the printing device to continue to function properly. For example, a replaceable component can be removed and another installed in a printer to provide a printing supply for the printing process.
Replaceable components can be manufactured with memory which can be placed on the component itself or within a label affixed to the component. This memory is typically used to store printer-related data that the printer reads to determine various printing parameters. For example, the memory may store the model number of the component so that the printer may recognize the cartridge as valid or invalid for use with that printer.
As documents are printed, the replaceable component is gradually depleted. The printer communicates with the memory of the replaceable component to detect, estimate, determine, and/or derive when a state of exhaustion has been reached. Once the replaceable component is deemed to have been exhausted, the printer will stop printing. The printer is also configured to resume printing when the replaceable component is replaced.
In making a judgment as to the exhaustion of a replaceable component, a safety margin is generally included that accounts for variables such as temperature, humidity, sensor inaccuracy, etc. The safety margin effectively decreases the likelihood of printing any portion of the complete printout with poor print quality. As such, the replaceable component may be sufficient to print some, and perhaps the entire print job with good or near-good print quality. For instance, if a printer is printing a one hundred (100) page print job and the toner in the toner cartridge is sensed as reaching its safety margin for a state of out toner at the ninetieth (90th) page, the remaining ten (10) pages will not be printed. If the remaining ten (10) pages could be printed by the printer, they would likely still be readable, possibly with lighter printed characters due to the low toner condition.
Once the printing device determines that the margin of safety for the replaceable component has been exceeded so as to establish an end-of-life condition, the printing stops. The cessation from printing can occur at any point in a print job that a user has requested and has been waiting for. If a user cannot locate or is otherwise unable to obtain or install the needed replaceable component, the user will not be able to obtain the desired complete printout. Frustration can arise for the user where only a draft copy of the complete print job is needed and the user is not particularly concerned with the resultant print quality. Consequently, there is a need for improved methods and printing devices that can provide the user with the desired complete printout after a replaceable component is estimated to have been exhausted.